COOKEVILLE, Tenn. -- A statewide endangered child alert was canceled after two missing sisters from North Carolina were found near Cookeville, Tenn., on Wednesday.

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Keara L. Hess, 12, and Sierra N. Hess, 11, missing since last Thursday, were traveling illegally in the company of their adoptive father Matthew Hess, 40.

At about 8:45 a.m, a driver, Laure Pemberton, was traveling west on Interstate 40 in Putnam County, when she saw a green Ford Explorer described in the endangered child alert. Pemberton contacted the Tennessee Highway Patrol by mobile phone immediately.

"Thanks to the keen observation of a Tennessee motorist who spotted a vehicle matching the description of the vehicle in the Endangered Child Alert, Tennessee State Troopers were able to locate the two girls and make a traffic stop and arrest," said THP Colonel Mike Walker in a press release. "Paramount to the successful recovery of the sisters was the motorist’s contacting the proper authorities. It serves as a great reminder of the importance of citizen involvement in Amber Alert cases."

Trooper Mark Jones and Trooper Mitilda Mahaney stopped the Explorer at about 9 a.m. on Interstate 40 at the 256 mile marker in Smith County.

When the troopers stopped Hess, his two adoptive daughters were both inside the vehicle. Troopers took Hess into custody, and he is being held in the Smith County Jail awaiting extradition back to North Carolina.

Hess will face charges of child abuse and two counts of contributing to the delinquency of a minor.

Keara is eight months pregnant and in need of emergency medical attention. She was scheduled to have a medical procedure the day she disappeared.

Keara and Sierra were taken to Riverview Hospital in Smith County for observation. Both girls are reported in good condition.

North Carolina Division of Social Services had issued a non-secure custody order authorizing the state to take custody of Keara and Sierra.

Law enforcement authorities had been looking nationwide for the girls, including several cities in middle Tennessee.

The girls' mother said she awoke Thursday and found a note from Hess that he was taking the girls to school, but they never made it there.